The invention relates to a pull-out guide for pulling a pull-out furniture part out of a basic furniture structure in a pull-out direction and for pushing the pull-out furniture part into the basic furniture structure counter to the pull-out direction, comprising at least a first and a second guide rail, which can be displaced relative to one another in and counter to the pull-out direction, wherein the first guide rail has a basic profile and at least one lateral-guidance unit, which is retained on the basic profile and has a lateral-guidance part, wherein the lateral-guidance part, in order to limit an amount of play of the second guide rail in relation to the first guide rail in at least one transverse direction running at right angles to the pull-out direction, interacts with at least one lateral-guidance surface of the second guide rail, and it is possible to adjust the position of the lateral-guidance part as seen in the transverse direction in relation to the basic profile of the first guide rail.
Pull-out guides serve for pulling a pull-out furniture part, such as a drawer, at least essentially rectilinearly out of a basic furniture structure. The pulling-out operation usually takes place in the horizontal direction, but other pull-out directions are also possible.
In general, a respective pull-out guide is provided on opposite sides of the pull-out furniture part, wherein the two pull-out guides are configured in a more or less mirror-inverted manner.
In particular running rollers which are arranged on at least one of the guide rails such that they can be rotated about axes or rolling-contact bodies, in particular in the form of balls, which are arranged in cages between running tracks of the guide rails are known for guiding the guide rails of pull-out guides in a displaceable manner in relation to one another. Sliding-guiding elements, if appropriate in conjunction with running rollers and/or rolling-contact bodies, are also known.
Such systems end up, both in respect of the dimensioning of the basic furniture structure, with deviations in the distance between the basic-structure-mounted guide rails, which are fastened on the basic furniture structure, on either side of the pull-out furniture part, and, in respect of the dimensioning of the pull-out furniture part, with deviations in the distance between the pull-out guide rails, which are fastened on either side of the pull-out furniture part. It is also the case that the pull-out guides themselves have certain deviations in their dimensions. These deviations are caused by tolerances during production of the various elements, by slight skewing of the furniture if the underlying surface on which the furniture is set out is not completely planar, by deviations in straightness of the structural elements used, and by flexing of the elements when subjected to loading during use. These deviations in the installation dimensions are compensated in different ways in the prior art.
In the case of known pull-out guides, in order to compensate for deviations in installation dimensions, the guide rails have a sufficiently large amount of play in relation to one another in the transverse direction, that is to say in the direction in which the pull-out guides fitted on either side of the pull-out furniture part are spaced apart. An amount of play of 1-3 mm is typically present on each side, and this means that, with conventional deviations in the installation dimensions, scraping noises or lateral friction do not occur. It is also the case that lateral-guidance elements in the form of sliding elements or rollers are known in order to reduce friction and noise even if there is contact in the transverse direction.
One disadvantage of such a design with relatively large amounts of lateral play is that, depending on the dimensions present in a specific installation, an amount of lateral play is noticeable to a more or less pronounced extent, in particular under a low load (=a low level of loading of the pull-out furniture part). In particular in the pull-out state, the lateral stability of such guide systems is deemed to be insufficient; the guidance system is “unstable”. Even in the closed state, there is no defined lateral position of the guide within the amount of design-specific lateral play, and there is no alignment of the positions of front panels located one above the other.
In particular roller guides (with running rollers mounted in a rotatable manner about axes), but also guides with rolling carriages and sliding elements, are designed with such an amount of lateral play.
Also known are guide systems, in particular ball guides, which, for design reasons, do not have any lateral play. Deviations in the installation dimensions in the transverse direction are compensated for by profile structures being flexible in the transverse direction. The disadvantage of these solutions is a very restricted level of tolerance compatibility. Even a deviation in the installation dimensions in the transverse direction of one millimeter results in high lateral forces and, despite laterally acting rolling-contact bodies (balls), in noticeably increased frictional forces, and therefore, for example, it is also possible for the function of a spring-controlled self-retracting mechanism to be adversely affected. It is also the case that the lateral flexibility present gives rise, in particular in the pulled-out state, to an unstable impression if manual loading is applied laterally (“yielding” appearance).
In the case of a further conventional design, the pull-out guides on either side of the pull-out furniture part itself are designed without any play in the transverse direction, for example by lateral-guidance rollers (which absorb the weight of the pull-out furniture part) being present in addition to load-bearing rollers. In order to compensate for different installation dimensions in the transverse direction, the pull-out furniture part here has an amount of play in the transverse direction in relation to the respective pull-out guide. The advantage of this design is the relatively high level of tolerance compatibility in the transverse direction. The disadvantage, however, is that the amount of lateral play present between the pull-out furniture part and the pull-out guides fitted on either side of the latter is noticeable to the user, in particular in the pulled-out state.
It is also known that the pull-out furniture part can be connected to the pull-out guide in different positions as seen in the transverse direction. Such a design can be gathered from EP 1 483 984 A9. Here, there are elements present which allow side-wall parts of the drawer to latch with the pull-out guide rail of the pull-out guide at different positions as seen in the transverse direction. One disadvantage of this arrangement is the comparatively complicated design with a large number of parts. It is also the case that available stowage space is lost as a result of the large width of the structure, since a number of wall thicknesses have to be accommodated in the design.
DE 25 49 444 A1 discloses a pull-out guide of the type mentioned in the introduction. Adjustable lateral-guidance parts in the form of sliding elements or else rollers are present in order to adjust an amount of play between two guide rails of a pull-out guide in relation to the transverse direction. A lateral-guidance unit, which retains the lateral-guidance part or mounts the same in a rotatable manner, is fitted on one of the two guide rails, and the lateral-guidance part interacts on one side with a lateral-guidance surface of the other of the two guide rails. So that they cannot be adjusted automatically by the action of drawer forces, the adjusting means for adjusting the lateral-guidance parts are of self-locking design. The adjusting means provided for adjusting the lateral-guidance part is, for example, an eccentric which can be inserted in different rotary positions into a housing of the lateral-guidance unit, wherein the inserted eccentric is prevented from rotating in relation to the housing by interacting protrusions and depressions (in the manner of interacting toothing formations). The complicated adjustment of the lateral-guidance parts is disadvantageous. It is also the case that the adjusting means, at least if they are arranged in a central or rear region of the pull-out guide, are accessible only with difficulty, if at all, when a drawer has been inserted. It is then possible, with the drawer removed, to carry out adjustment on a trial-and-error basis, wherein it is only once the drawer has been inserted that it is established whether the adjustment is correct or whether readjustments have to be made. In addition to manually activated adjusting means, DE 25 49 444 A1 also mentions hydraulically or pneumatically actuated adjusting means. Such designs, however, are very costly.
DE 26 07 435 A1 likewise discloses a pull-out guide with adjustable lateral-guidance parts. In one of the embodiments disclosed, sliding pieces of different dimensions can be used in order to adjust the amount of play between the guide rails. Also disclosed is a sliding piece which is designed in the form of an eccentric and can be used in different rotary positions. Also illustrated is a rotary piece, on which the lateral-guidance rollers are mounted in a rotatable manner. The rotary piece can be fastened in different rotary positions on a bearing part, for example by the axis of rotation being provided in the form of a screw which is tightened once the position of the rotary piece has been adjusted. The lateral-guidance parts which can be gathered from this document likewise interact on one side with a lateral-guidance surface of the other guide rail. It is also the case for the pull-out guides known from DE 26 07 435 A1 that relatively complicated manual adjustment is necessary.
Similar designs can be gathered from DE 77 10 556 U. Lateral-guidance parts which are designed in the form of sliding elements and interact on one side with a lateral-guidance surface on the other guide rail are adjusted in position in relation to the transverse direction by means of manually activated adjusting elements. The adjusting elements disclosed are an adjusting screw and an eccentric disk, which can be arrested in a stepwise manner by means of toothing formations.